Radiator Black Gloss Paint is just the right viscosity to spray-paint your radiator without damaging it Won't block airflow between cooling fins Won't interfere with heat transfer Acrylic enamel (80% + gloss level) Withstands 300 degreesF Standard engine paints are too thick for use on a radiator because they can interfere with heat transfer, and block airflow between the cooling fins. But Radiator Black Gloss is specifically formulated for your radiator, heater core and air conditioning condenser.